Anesthetic compound



Patented Dec. 13, 1927.

UNITED STATES NORMAN A. HANSEN, OF LAKE BIIUFIF, ILLINOIS, ASSIGNOR TO ABBOTT LABORATORIES,

PATENT OFFICE.

O1 NORTH CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ANESTHETIC COMPOIJ'ND.

' No Drawing.

I Z G L 2) 3 4 9) z] z i a a As is well known, the salts of anaesthetic bases may vary widely in their solublhties,

10 stability, hydrogen ion concentrations in solution, irritating properties, and eliiciency. In the particular case of para-am1no-benzoyl-(li-n-butylamino propanol (for convenience called X), the hydrochloride is soluble in cOld water to the extent of less than 1%.

It has a pH of about 5.5, and when used as an anaesthetic, it may produce a temporary smarting, lasting for'several seconds. Other salts of X, the pH of which is nearer 7, and

which are, therefore, less irritating, such as the succinate or lactate, are not entirel stable in solution, undergoing hydrolysls upon boiling, so that some of the anaesthetic base separates as oily droplets. It is also known that anaesthetic salts are frequently more eflicient, the higher the pH values.

It has now been found that the tartrate of X is free from the above objections. It is readily and sufiiciently soluble in water, giving stable solutions which may be sterilized without appreciable decomposition; The aqueous solutions of X tartrate have a pH of about 6.8, making them well tolerated when injected or applied topically, and practi- Application filed December 18, 1926. Serial No. 155,769.

cally free from irritating qualities. Furthermore, X tartrate, while more efiicient than the mineral acid salts of the anaesthetic base, is also somewhatless toxic, so that its use is attended with greater safety.

.lletlzod 0 f preparation-A solution of grams of tartaric acid in 1000 cc. of water is heated to about C., and to this solution is added 306 grams of the anaesthetic base. The anaesthetic base goes into solution, and when the solution is cooled, the tartrate of the anaesthetic crystallizes out. After centrifuging off the crystals, they are purified by recr stallization from alcohol. The pure w iite crystals melt at- 144145 C. The product is readily soluble in water, producing stable solutions.

Both the water used to dissolve the tartaric acid. and the temperature at which the anaesthetic base is added, may be varied within rather wide limits. Other solvents than water may also be used for dissolving the components.

I claim as my invention:

1. As a new product of manufacture, the tartra'te of para-amino-benzoyl-di-n-buty amino p ropanol, having the formula ZCJL 2) 3 9) 212 4 0 0- 2. As a new anaesthetic compound, the tartrate of para-aminobenzoyl-d1-n-butylamino propanol, which is a white crystalline solid, melting at E L-145 C.

NORMAN A. HANSEN. 

